Our favorite Smart TV platform, Roku TV , isn't found on TVs made by Samsung, LG, Sony Vizio or any of the other major-brand TVs sold in the US.

It's on TVs by TCL, the number one domestic TV brand in China and one that's fast making inroads in other countries.

Today TCL announced pricing and availability on its latest group of Roku TVs, and true to form they're dang cheap, er, "inexpensive."

The line consists of the 32-inch 32S3700 ($219), the 48-inch 48S3700 ($429) and the 55-inch 55S3700 ($598). They'll be available at major retailers starting late March and early April.

In my four-star review of their predecessors from last year, the TCL FS4610R series , I said Roku TV "delivers the simplest, slickest, most comprehensive smart-TV experience on the market. Its superb user interface puts apps and streaming video on the same plane as regular TV. It's also less expensive than just about any other smart TV."

The new S3700 series' suggested retail prices are similar to those of the 2014 FS4610R. At Amazon the price on the 48-inch sizes in the two series is identical, while the older 55-incher is about $70 less than the MSRP of the new one. Meanwhile the older 32-inch size is sold out, and there's no 40-inch size in the new series (the older one is still available for around $350 from some vendors).

Aside from minor styling tweaks, the biggest being a different-shaped stand base, there's very little difference between the older FS4610R and new S3700 series. The 32-inch size has the same 720p resolution and 60Hz refresh rate specification as its predecessor, and the 48-inch and 55-inch sizes get 1080p panels with 120Hz refresh rates. TCL told me they use 60Hz panels with scanning backlights to get to "120Hz." Such specsmanship is par for the course these days on models like Vizio's E series and some LG sets.

TCL's press release also mentioned two other series of step-up Roku TVs coming soon, the S3800 (32, 40, 48 and 55 inches) and S3850 series (32, 40, 48 and 50 inches) launching later in the second quarter. Again design is the chief difference, with the S3800 getting "a new ultra-modern design with a quad pedestal stand" (paging Samsung) and the S3850 getting "premium design with a metallic finish offered in gunmetal and an all-aluminum quad pedestal stand." Pricing for the S3800 and S3850 was not announced.

Also mentioned were the 4K TCL Roku TVs first announced at CES. They're still said to be under development for some unspecified time in the future.

Currently Roku TV is available on sets made by TCL and Hisense, while other brands coming later in 2015 include Haier and Best Buy house brand Insignia.